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arXiv · 2503.10767

Simple Hamiltonians for Matrix Product State models

Norbert Schuch·Andras Molnar·David Perez-Garcia
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Abstract

Matrix Product States (MPS) and Tensor Networks provide a general framework for the construction of solvable models. The best-known example is the Affleck-Kennedy-Lieb-Tasaki (AKLT) model, which is the ground state of a 2-body nearest-neighbor parent Hamiltonian. We show that such simple parent Hamiltonians for MPS models are, in fact, much more prevalent than hitherto known: The existence of a single example with a simple Hamiltonian for a given choice of dimensions already implies that any generic MPS with those dimensions possesses an equally simple Hamiltonian. We illustrate our finding by discussing a number of models with nearest-neighbor parent Hamiltonians, which generalize the AKLT model on various levels.

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Norbert Schuch, Andras Molnar, David Perez-Garcia. 2025-03-13. Simple Hamiltonians for Matrix Product State models. https://arxiv.org/abs/2503.10767

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